主

1. Origins, structure, and basic meaning

• Structure: Spelling: 主. Reading: ぬし. Core meaning: owner; master.
• Basic usage: Representative examples: 留守だった家の主が夕方に戻ってきた / この池の主だと呼ばれる大きな魚がいる.

2. Common pitfalls and similar expressions

• Owner and dominant inhabitant
  • It can mean the owner or master of a house, and it can figuratively name a large, long-established creature that dominates a place, as in 池の主.